Also, control group had a relatively lower abundance of Desulfobacterota which is known to be butyrate metabolizing (Suzuki et al. 2010), and Bifidobacterium which positively correlate with AD and tau protein in the brain (Shen et al. 2017; Saji et al. 2019; Hung et al. 2022; Sheng et al. 2022; Ferreiro et al. 2023). The gene discussed is MAPT; the disease is Alzheimer disease.